Поменять Http Header - Server: nginx/1.13 для сайта

Нужно для одного из сайтов поменять значение Server:

http://dl4.joxi.net/drive/2018/01/10/0022/0836/1487684/84/8481c91084.jpg

Вообще идея сделать так:

http {

    more_set_headers "Server: Сюда ввести, что надо";

    server_tokens off; 

}

Но застрял на этапе установки nginx-extras.

На сервере nginx, пробовал:

root@45:~# aptitude install nginx-extras

The following NEW packages will be installed:

  nginx-extras{b}

0 packages upgraded, 1 newly installed, 0 to remove and 25 not upgraded.

Need to get 715 kB of archives. After unpacking 1,597 kB will be used.

The following packages have unmet dependencies:

 nginx-extras : Depends: nginx-common (= 1.6.2-5~bpo70+1) but it is not going to                           be installed.

                Depends: libluajit-5.1-2 which is a virtual package.

The following actions will resolve these dependencies:

     Keep the following packages at their current version:

1)     nginx-extras [Not Installed]

Accept this solution? [Y/n/q/?] Y

No packages will be installed, upgraded, or removed.

0 packages upgraded, 0 newly installed, 0 to remove and 25 not upgraded.

Need to get 0 B of archives. After unpacking 0 B will be used.

Вот ещё вывод:

root@45:~# apt-get install nginx-extras

Reading package lists... Done

Building dependency tree

Reading state information... Done

Some packages could not be installed. This may mean that you have

requested an impossible situation or if you are using the unstable

distribution that some required packages have not yet been created

or been moved out of Incoming.

The following information may help to resolve the situation:

The following packages have unmet dependencies:

 nginx-extras : Depends: nginx-common (= 1.6.2-5~bpo70+1) but it is not going to be installed

                Depends: libluajit-5.1-2 but it is not installable

E: Unable to correct problems, you have held broken packages.

Может это быть из-за того, что в sources list где-то ispmanagerские репозитории?

В общем, туплю что-то. Кто может помочь и что по оплате?